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Date: Thu, 7 Aug 2025 17:31:11 -0700 (PDT)
X-X-Sender: jeremyd AT resin DOT csoft DOT net
To: cygwin AT cygwin DOT com
Subject: getting the on-disk case for a path
Message-ID: <36a0093c-fc8b-f268-9cbf-71c1c1268ef7@jdrake.com>
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From: Jeremy Drake via Cygwin <cygwin AT cygwin DOT com>
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Sender: "Cygwin" <cygwin-bounces~archive-cygwin=delorie DOT com AT cygwin DOT com>

On a case-insensitive but case-preserving filesystem, is there a Cygwin
API to get the on-disk case for a given path?  It seems like `realpath`
ought to do it but running
$ touch case-test
$ realpath CASE-TEST
returns CASE-TEST.  Regardless, canonicalize_file_name or realpath may not
be what I want because it would dereference symlinks.

Background: I'm trying to debug some test failures in Clang, due to a
warning that's supposed to be issued when you #include "foo.h" but the
file on disk that it opened is "Foo.h".

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